Cassini High Rate Detector (HRD) Standard Data Products and Archive Volume Software Interface Specification Version 1.1 November 26, 2007 Carol Neese Mark Sykes Planetary Science Institute, Tucson AZ 85719-2395 IO-AR-01 Cassini High Rate Detector (HRD) Standard Data Products and Archive Volume Software Interface Specification Version 1.1 November 26, 2007 Approved: ____________________________________ _____________ Thanasis Economou Date HRD Acting Principal Investigator ____________________________________ _____________ Elmain Martinez Date Cassini Archive Data Engineer ____________________________________ _____________ Mike A�Hearn Date PDS Small Bodies Node PI Distribution List M. A�Hearn P. DiDonna T. Economou E. Martinez Document Change Log Change Marked provisional label as final Date Nov. 26, 2007 Affected Portions Section 6 Acronyms and Abbreviations ASCII American Standard Code for Information Interchange CDA Cosmic Dust Analyser CODMAC Committee on Data Management and Computation DA Dust Analyser DFMI Dust Flux Monitor Instrument DUCMA Dust Counter and Mass Analyzer Instrument HRD High Rate Detector JPL Jet Propulsion Laboratory NASA National Aeronautics and Space Administration OLAF On-Line Archiving Facility PDS Planetary Data System PI Principal Investigator PVDF Polyvinylidene Fluoride SBN Small Bodies Node SFDU Standard Formatted Data Unit SIS Software Interface Specification TBD To Be Determined Table of Contents 1. Introduction 1 1.1. Purpose and Scope 1 1.2. Contents 1 1.3. Applicable Documents and Constraints 1 2. Data Product Characteristics 1 2.1. Instrument Overview 1 2.2. Data Products 2 2.3. Data Processing 3 2.4 Calibration 4 3. Archive Volumes 4 3.1. Generation 4 3.2. Data Transfer 5 3.3. Review and Revision 5 3.4. Data Volume Architecture 6 4. Cognizant Persons 7 5. References 7 6. Sample HRD Product Label 8 1. Introduction 1.1. Purpose and Scope This document describes the format and the content of the Cassini High Rate Detector (HRD) products as archived in the Small Bodies Node (SBN) in the Planetary Data System (PDS). The data products stored in the PDS are a subset of the holdings of the CDA (Cosmic Dust Analyzer) team database in Heidelberg, Germany, and the archive is produced by the HRD team at the University of Chicago. This Software Interface Specification (SIS) is intended to provide enough information to enable users to understand and use the HRD data products as stored in the PDS. The users for whom this SIS is intended are software developers of the programs used in generating the HRD products and scientists who will analyze the data, including those associated with the Cassini- Huygens Project and those in the general planetary science community. 1.2. Contents The High Rate Detector (HRD) is an independent part of the Cosmic Dust Analyzer (CDA) instrument on the Cassini orbiter that studies the physical properties of dust particles hitting the detector. This Data Product SIS describes how the HRD instrument acquires its data, and how the data are processed. This document specifically discusses the high level data subset, which is stored in the PDS. 1.3. Applicable Documents and Constraints This Data Product SIS is responsive to the following Cassini documents: 1 Cassini/Huygens Program Archive Plan for Science Data, PD 699-068. The reader is referred to the following documents for additional information: 1 Planetary Data System Data Preparation Workbook and Standards Reference Version 3.7, JPL D-7669. 2 The Cassini Cosmic Dust Analyser, Srama et al., SSR Volume 114, p. 465-518, December 2004. 2. Data Product Characteristics 2.1. Instrument Overview The High Rate Detector (HRD) is part of the Cosmic Dust Analyzer (CDA) on the Cassini mission payload. The overall objective of the HRD is to carry out quantitative measurements of particle flux and mass distribution throughout the Saturn ring system. The particle impact rate and particle mass distribution will be determined with respect to Saturnian distances, distance from the rings, and to magnetospheric coordinates. The particle mass range covered by the HRD (assuming a particle impact velocity of 15 km/s) ranges from 8x10-13 to 8x10-8 g for differential and cumulative flux measurements, and > 8x10-8 g for cumulative flux measurements. The HRD was designed, built and tested at the University of Chicago and measures differential and cumulative particle fluxes. The HRD has a high counting rate capability (up to 10^4 random impacts/second with <5% corrections) which will be particularly important during Saturn ring plane crossings, where fluxes are large enough to saturate the counting rate of the DA (Dust analyzer) (~1 counts/sec). The HRD has significant inheritance from the University of Chicago Dust Counter and Mass Analyzer instrument (DUCMA) flown earlier on the Vega-1 and Vega-2 spacecraft to Comet Halley (Perkins et al., 1985), and from the Dust Flux Monitor Instrument (DFMI) on the Stardust mission (Tuzzolino et al. 2003). The instrument employs the dust particle detection technique described by Simpson and Tuzzolino (1985) and consists of two polyvinylidene fluoride (PVDF) sensors with associated electronics. The sensors are mounted on the front of the HRD electronics box and the HRD detects individual particles impacting the PVDF sensors and provides continuous measurements of cumulative particle fluxes for particle masses greater than four mass thresholds for each of the two sensors. The HRD is an independent instrument containing its own memory and processor. The only interface to the Dust Analyzer (DA) of the CDA is via the power and data cables. HRD power is supplied by the DA main electronics and data transfer responds by latching the appropriate data into the HRD data output register. The latching of the data generates an interrupt to DA indicating that the data is ready to be read by DA and stored into DA memory. The HRD is rigidly mounted to the DA so that as the CDA turntable is rotated, the HRD scans different particle arrival directions. The HRD pointing is exactly the same as the DA pointing. 2.2. Data Products The HRD data products are all ASCII (American Standard Code for Information Interchange) tables and include raw, processed, and calibration files. Also included in the archive are tables of instrument on-off times, and tables of hourly instrument pointing and spacecraft position. A sample data label for the processed files appears at the end of this document. This sample data label includes column definitions for each of the columns in the data tables. The format of the raw and calibration files is the same as that for the processed files, but without the final three columns which give a quality code and the threshold mass and particle diameter. Raw files contain all events for the time period covered each file, including calibration and noise events. Each event in the raw files is assigned a unique event number. The calibration files contain the flight calibration events which have been extracted from the raw files. The processed files contain the events from the raw files with the calibration and noise events removed. The file counts and sizes will be relatively small. The greatest data volume will occur in 2005 during the Saturn ring plane crossing, with 36 data files each less than 500 kb. Note that the HRD files after 2005-248 are somewhat increased in size because the larger PVDF sensor M was hit by a very big dust particle that resulted in a change to the lowest mass threshold (M1), causing the M1 counter to become somewhat noisier. All data products and associated documentation will be generated by the HRD team. The PDS SBN will assist in the definition and development of first delivery products and their associated PDS documentation, which will act as templates for subsequent updates. When new products are developed by the HRD team, PDS SBN will likewise assist in the definition and development of those products and their associated PDS documentation in preparation for their initial delivery. All the data products described by this SIS will be included in a single data set. Ongoing deliveries of data will be accomodated in cumulative versions of the data set, i.e. the latest version of the data set will include all the data archived so far, superseding earlier versions. 2.3. Data Processing This documentation uses the "Committee on Data Management and Computation" (CODMAC) data level numbering system. The raw data files referred to in this document are considered "level 2" or "Edited Data" (equivalent to NASA level 0). The data files are generated from level 1 or "Raw Data" which is the telemetry packets within the project specific Standard Formatted Data Unit (SFDU) record. The processed files have added columns for mass and particle size determined from the calibration described in the instrument document, and are thus CODAMC level 3. Refer to Table 1. Table 1. Processing Levels for Science Data Sets NASA CODMAC Description Packet data Raw - Level 1 Telemetry data stream as received at the ground station, with science and engineering data embedded. Level-0 Edited - Level 2 Instrument science data (e.g., raw voltages, counts) at full resolution, time ordered, with duplicates and transmission errors removed. Level 1-A Calibrated - Level 3 Level 0 data that have been located in space and may have been transformed (e.g., calibrated, rearranged) in a reversible manner and packaged with needed ancillary and auxiliary data (e.g., radiances with the calibration equations applied). Level 1-B Resampled - Level 4 Irreversibly transformed (e.g., resampled, remapped, calibrated) values of the instrument measurements (e.g., radiances, magnetic field strength). Level 1-C Derived - Level 5 Level 1A or 1B data that have been resampled and mapped onto uniform space-time grids. The data are calibrated (i.e., radiometrically corrected) and may have additional corrections applied (e.g., terrain correction). Level 2 Derived - Level 5 Geophysical parameters, generally derived from Level 1 data, and located in space and time commensurate with instrument location, pointing, and sampling. Level 3 Derived - Level 5 Geophysical parameters mapped onto uniform space-time grids. 2.4 Calibration The HRD calibrations are similar to those for the Dust Flux Monitor Instrument (DFMI) on the Stardust mission. The pre-flight calibrations were carried out with dust particle accelerators in Heidelberg and Munich. During the calibration at Heidelberg, iron particles in the velocity range of 1-12 km/sec were used, while at the Munich accelerator glass particles of a similar velocity range were used. The mass and particle diameters corresponding to each detector threshold as derived from these calibrations are given in the HRD instrument catalog file. In addition to laboratory calibration, in-flight pulser calibrations are performed periodically to ascertain the performance of the electronic system of the HRD instrument. These in-flight calibration events are included in the raw data files and are also extracted to separate calibration files in the archive. If the thresholds are changed over the course of the mission, this will be documented in a threshold change log. 3. Archive Volumes 3.1. Generation The HRD Data Product Archive Collection and its updates are produced by the HRD Instrument Team in cooperation with the Small Bodies Node (SBN) of the PDS. The Archive Collection will include data acquired during the Cruise phase as well as during the Tour. The SBN and the HRD team will collaborate to design the PDS documentation (label, catalog, and index) files associated with the initial data delivery by the HRD team. SBN and the HRD team together will also identify how these files are to be updated in subsequent deliveries. This procedure will also be followed with new data products as they become available. The HRD team will include documentation files (and subsequent updates) with their deliveries. All data formats are based on the Planetary Data System standards as documented in the PDS Standards Reference. SBN will generate the data labels and volume structure of the HRD archive using the On-Line Archiving Facility (OLAF). The HRD team will deliver data products to SBN in a form compatible with OLAF and with the archive design mutually agreed upon by SBN and the HRD team. Higher level products are not within the scope of this SIS but will be covered under a separate SIS and be delivered to SBN by the HRD team as standard data products through OLAF. 3.2. Data Transfer Deliveries will be made to the PDS in accordance with the schedule defined in the Cassini/Huygens Program Archive Plan for Science Data, PD 699-068, as shown here: From first day of: Through last day of: Delivery date: Oct 1997 Mar 2006 (already delivered) Apr 2006 Jun 2006 Apr. 1, 2007 July 2006 Sep 2006 Jul. 1, 2007 Oct 2006 Dec 2006 Oct. 1, 2007 Jan 2007 Mar 2007 Jan. 1 2008 Apr 2007 Jun 2007 Apr. 1 2008 Jul 2007 Sep 2007 Jul. 1, 2008 Oct 2007 Jul 2008 Sep. 1, 2008 3.3. Review and Revision The archive validation procedure described in this section applies to volumes generated during all phases of the mission. All data archived by the PDS are validated by use of the PDS peer review procedures. The data and documentation will be subject to PDS internal review followed by an external peer review. The external review consists of at least two scientists having interest in the products being generated by the HRD who are associated with neither the HRD team nor the PDS. Reviewers are selected by the PDS with input from the HRD team. In the event that the contents of a volume are found to contain errors, the reviewers can recommend one of two courses of action: fix the files or publish as is with a note in the ERRATA.TXT file. If the errors are minor, typically minor errors in the documentation, the volume can be published if the appropriate notes added to the volume�s errata file and the error(s) are corrected on subsequent volumes. If the errors are major, typically involving errors in the data themselves, the corrections constitute liens against the data set that must be resolved before the data set can be ingested by the PDS. In that event, the volume must be corrected and regenerated by the HRD team. 3.4. Data Volume Architecture Data will be delivered on DVD or DVD-image with the following directory architecture: VOLUME_ID ----------AAREADME.TXT , VOLDESC.CAT, ERRATA.TXT | |--/DATA [this directory contains all data products and their labels.] | |--/raw [raw data files] |--/calibrate [calibration files] |--/processed [processed files] |--/onoff [instrument on-off times] |--/pointing [instrument pointing and s/c positions] | |--/CATALOG [this directory contains the data set, instrument, | and mission catalog files.] | |--/INDEX [this directory contains the index files for the volume.] | |--/DOCUMENT [this directory contains the document you are reading.] 4. Cognizant Persons Table 4.1 � HRD PDS Archive Collection Support Staff HRD Team Dr. Thanasis Economou Laboratory for Astrophysics and Space Research University of Chicago 933 East 56th Street Chicago IL 60637 773/702-7829 tecon@tecon.uchicago.edu Mr. Pasquale DiDonna Laboratory for Astrophysics and Space Research University of Chicago 933 East 56th Street Chicago IL 60637 773/834-3774 pdidonna@ucec.uchicago.edu Asteroid/Dust Subnode of the SBN, Planetary Science Institute Dr. Carol Neese Planetary Science Institute 1700 East Ft. Lowell, Suite 106 Tucson, AZ 85719-2395 520/622-6300 neese@psi.edu PDS Engineering Node Steven Adams, PDS Cassini Data Engineer Jet Propulsion Laboratory, MS Pasadena, CA 818/354-2624 Steven.L.Adams@jpl.nasa.gov 5. References Perkins, M.A., J.A. Simpson, and A.J. Tuzzolino. Cometary and Interplanetary Dust Experiment on the Vega Spacecraft Mission to Halley�s Comet. Nucl. Instr. and Methods in Phys. Res., A239, 310. 1985. Simpson, J.A. and A.J. Tuzzolino. Polarized Polymer Films as Electronic Pulse Detectors of Cosmic Dust Particles. Nucl. Instr. and Methods in Phys. Res. A236, 187-202, 1985. Srama, R., T.J. Ahrens, N. Altobelli, S. Auer, J.G. Bradley, and 35 others. The Cassini Cosmic Dust Analyzer. Space Science Reviews 114, 465-518, 2004. Tuzzolino, A.J., T.E. Economou, R.B. McKibben, J.A. Simpson, J.A.M. McDonnell, and 6 others. The Dust Flux Monitor Instrument for the STARDUST Mission to Comet Wild-2. Geophys. Res. 108, no. 12, doi:10.1029/2003JE002019, 2003. 6. Sample HRD Product Label PDS_VERSION_ID = PDS3 RECORD_TYPE = "FIXED_LENGTH" RECORD_BYTES = 161 FILE_RECORDS = 6 ^TABLE = "hrd_2003_037_111_prc.tab" DATA_SET_ID = "CO-D-HRD-3-COHRD-V1.0" PRODUCT_NAME = "HRD_2003_037_111_PRC" PRODUCT_ID = "PROCESSED_2003_HRD_2003_037_111_PRC_TAB" INSTRUMENT_HOST_ID = "CO" INSTRUMENT_HOST_NAME = "CASSINI ORBITER" INSTRUMENT_ID = "HRD" INSTRUMENT_NAME = "HIGH RATE DETECTOR" TARGET_NAME = "DUST" TARGET_TYPE = "DUST" START_TIME = 2003-037T22:22:18.329 STOP_TIME = 2003-111T09:51:05.968 PRODUCT_CREATION_TIME = 2007-01-31 /* File uploaded to OLAF */ REFERENCE_KEY_ID = "SRAMAETAL2004" OBJECT = TABLE ROWS = 6 ROW_BYTES = 161 INTERCHANGE_FORMAT = "ASCII" COLUMNS = 28 DESCRIPTION = "Processed Cassini HRD data file. Data files in the 'processed' subdirectory have had calibration events and noisy events removed. On 2005-248 there occurred an M4 event in the large detector which resulted in a noisy M1 threshold. Since then, all M1 events are considered to be noise and have been removed from the processed data unless the M2 threshold is triggered or the small detector m1 threshold is triggered or the large detector High Mass is set. The processed files have filenames of the form hrd_yyyy_doy_doy_prc.tab and include data within the date range specified." OBJECT = COLUMN COLUMN_NUMBER = 1 NAME = "EVENT_CODE" DESCRIPTION = "A unique code assigned to each event in the raw data files to enable tracking an event through the calibration and processed files. The event code has a range from A1-Z999999999. The letter corresponds to the year such that A events are in 2000, B events in 2001, etc. The numbers are sequential starting with 1 within the year. The same event listed in the processed or calibration files will have the same event code." DATA_TYPE = "CHARACTER" START_BYTE = 1 BYTES = 10 FORMAT = "A10" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 2 NAME = "EVC" DESCRIPTION = "The event counter (EVC) generated by the HRD data processing software is a 3 digit integer with a range of 0 to 256. When the data processing software finds an A5A5A5 sync pattern or the counter is greater than 256, the counter is reset to 0." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 12 BYTES = 3 FORMAT = "I3" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 3 NAME = "SYC" DESCRIPTION = "The HRD Sync (SYC) consists of 3 bytes which contain A5A5A5 or EVEVEV. A5A5A5 indicates the start of an HRD Cruise Mode or Encounter Mode header, and EVEVEV indicates a discrete event. A5A5A5 is part of the HRD data, while EVEVEV is generated by the HRD data processing software to indicate a discrete event." DATA_TYPE = "CHARACTER" START_BYTE = 16 BYTES = 6 FORMAT = "A6" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 4 NAME = "TP" DESCRIPTION = "The HRD temperature indicator (TP) has a range from 0 to 99. The temperature is read by the Dust Analyzer (DA) instrument and given to HRD. The formula to convert the temperature code (TP) into degree Celsius is Temp = 40 - TP * 0.5. Example: A TP value of 63 results in a Temperature of -8.5 degC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 23 BYTES = 2 FORMAT = "I2" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 5 NAME = "STAT" DESCRIPTION = "The hex code for the eight bit status word has two bytes, the first corresponding to binary status word bits 4-7 and the second corresponding to status word bits 0-3. Since status word bits 4 and 5 are always zero, the first hex byte has only four possibilities: First SW bits hex byte: 7654: Description: 0 0000 D1 and D2 Threshold set to High Mass 4 0100 D1 Threshold set to Low Mass and D2 Threshold set to High Mass 8 1000 D1 Threshold set to High Mass and D2 Threshold set to Low Mass C 1100 D1 and D2 Thresholds set to Low Mass The second hex byte corresponds to binary status word bits 0-3 as follows: Second SW bits hex byte: 3210: Description: 0 0000 Cruise Mode 1 0001 .1 sec Encounter Mode time resolution 2 0010 .2 sec Encounter Mode time resolution 3 0011 .3 sec Encounter Mode time resolution 4 0100 .4 sec Encounter Mode time resolution 5 0101 .5 sec Encounter Mode time resolution 6 0110 .6 sec Encounter Mode time resolution 7 0111 .7 sec Encounter Mode time resolution 8 1000 .8 sec Encounter Mode time resolution 9 1001 .9 sec Encounter Mode time resolution A 1010 1 sec Encounter Mode time resolution B 1011 Gain 1 In-Flight Calibration C 1100 Gain 2 In-Flight Calibration D 1101 Gain 3 In-Flight Calibration E 1110 Gain 4 In-Flight Calibration Example: If hex status word is C0, binary status word bits 4-7 are C = 1100 and binary status word bits 0-3 are 0 = 0000. Consulting the table, the D1 and D2 Thresholds are set to Low Mass, and the status is Cruise Mode." DATA_TYPE = "CHARACTER" START_BYTE = 26 BYTES = 2 FORMAT = "A2" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 6 NAME = "OBS_TIME" DESCRIPTION = "Universal Time Coordinated (UTC) of the SC/CLK time" DATA_TYPE = "TIME" START_BYTE = 29 BYTES = 21 FORMAT = "A21" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 7 NAME = "SC_CLK" DESCRIPTION = "The 32-bit spacecraft clock (SC_CLK) only appears in the 32-byte HRD cruise mode header. It has a range of 0 - 4294967295 seconds. When HRD receives the spacecraft clock from the Dust Analyzer (DA) instrument, HRD stores the spacecraft clock and the HRD 32-bit header clock at the same time. This insures that the two clocks are in sync with each other." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 51 BYTES = 10 FORMAT = "I10" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 8 NAME = "HD_CLK" DESCRIPTION = "The HRD header clock (HD_CLK) appears in the 32-byte HRD cruise mode header or the 24-byte encounter mode header. When HRD is in cruise mode, the clock is 32 bits long and has a range of 0 - 4294967295 seconds. If HRD is in encounter mode, the clock is 27 bits long and has a range of 0 - 134217727 seconds. In cruise mode the header clock is only updated when HRD receives the spacecraft time. If HRD is in encounter mode then the clock is updated for every encounter mode read out. On HRD power on the HD/CLK is set to zero." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 62 BYTES = 10 FORMAT = "I10" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 9 NAME = "CLK" DESCRIPTION = "The HRD 21-bit clock (CLK) has a range of 0 - 2097151 seconds. If SYC is A5A5A5, this column shows the first 21 bits of HD_CLK, and if SYC is EVEVEV it shows the 21-bit clock from the discrete event. The HD/CLK and CLK are generated by the same time source on the HRD instrument. The only difference is that the HD/CLK is stored when HRD receives the spacecraft clock and the CLK is stored when a dust particle impact is recorded." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 73 BYTES = 7 FORMAT = "I7" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 10 NAME = "BIG_M1" DESCRIPTION = "Large detector M1 threshold is either 1 or 0. 1 indicates that the M1 threshold latch has been triggered. Every time the threshold is exceeded, this will be indicated in the CM1 counter (BIG_CM1)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 81 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 11 NAME = "BIG_M2" DESCRIPTION = "Large detector M2 threshold is either 1 or 0. 1 indicates that the M2 threshold latch has been triggered. For M2 to trigger, M1 must be triggered. Every time the threshold is exceeded, this will be indicated in the CM2 counter (BIG_CM2)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 83 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 12 NAME = "BIG_M3" DESCRIPTION = "Large detector M3 threshold is either 1 or 0. 1 indicates that the M3 threshold latch has been triggered. For M3 to trigger, M1 and M2 must be triggered. Every time the threshold is exceeded, this will be indicated in the CM3 counter (BIG_CM3)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 85 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 13 NAME = "BIG_M4" DESCRIPTION = "Large detector M4 threshold is either 1 or 0. 1 indicates that the M4 threshold latch has been triggered. For M4 to trigger, M1, M2, and M3 must be triggered. Every time the threshold is exceeded, this will be indicated in the CM4 counter (BIG_CM4)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 87 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 14 NAME = "SMALL_M1" DESCRIPTION = "Small detector m1 threshold is either 1 or 0. 1 indicates that the m1 threshold latch has been triggered. Every time the threshold is exceeded, this will be indicated in the Cm1 counter (SMALL_CM1)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 89 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 15 NAME = "SMALL_M2" DESCRIPTION = "Small m2 threshold is either 1 or 0. 1 indicates that the m2 threshold latch has been triggered. For m2 to trigger, m1 must be triggered. Every time the threshold is exceeded, this will be indicated in the Cm2 counter (SMALL_CM2)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 91 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 16 NAME = "SMALL_M3" DESCRIPTION = "Small m3 threshold is either 1 or 0. 1 indicates that the m3 threshold latch has been triggered. For m3 to trigger, m1 and m2 must be triggered. Every time the threshold is exceeded, this will be indicated in the Cm3 counter (SMALL_CM3)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 93 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 17 NAME = "SMALL_M4" DESCRIPTION = "Small m4 threshold is either 1 or 0. 1 indicates that the m4 threshold latch has been triggered. For m4 to trigger, m1, m2, and m3 must be triggered. Every time the threshold is exceeded, this will be indicated in the Cm4 counter (SMALL_CM4)." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 95 BYTES = 1 FORMAT = "I1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 18 NAME = "BIG_CM1" DESCRIPTION = "Large detector D1 threshold M1 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the CM1 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is only updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 97 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 19 NAME = "BIG_CM2" DESCRIPTION = "Large detector D1 threshold M2 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the CM2 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is only updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 103 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 20 NAME = "BIG_CM3" DESCRIPTION = "Large detector D1 threshold M3 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the CM3 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 109 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 21 NAME = "BIG_CM4" DESCRIPTION = "Large detector D1 threshold M4 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the CM4 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 115 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 22 NAME = "SMALL_CM1" DESCRIPTION = "Small detector D2 threshold m1 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the Cm1 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is only updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 121 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 23 NAME = "SMALL_CM2" DESCRIPTION = "Small detector D2 threshold m2 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the Cm2 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is only updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 127 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 24 NAME = "SMALL_CM3" DESCRIPTION = "Small detector D2 threshold m3 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the Cm3 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is only updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 133 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 25 NAME = "SMALL_CM4" DESCRIPTION = "Small detector D2 threshold m4 16 bit counter has a range of 0 - 65535. When there is a dust particle event above threshold the Cm4 counter will be incremented and will roll over to 0 when the maximum count is reached. The content of the counter is only updated when the A5A5A5 sync pattern occurs in SYC." DATA_TYPE = "ASCII_INTEGER" START_BYTE = 139 BYTES = 5 FORMAT = "I5" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 26 NAME = "QUALITY_CODE" DESCRIPTION = "The quality code indicates a discrepancy with the data line and is set to * if any one of the following obtain: 1. Missing latch data. 2. Counters change with no latch data. 3. Higher threshold triggered and lower threshold did not. The value of - indicates the quality code is not set and the above criteria do not apply." DATA_TYPE = "CHARACTER" START_BYTE = 145 BYTES = 1 FORMAT = "A1" END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 27 NAME = "THRESHOLD_MASS" DESCRIPTION = "The particle mass corresponding to the detector threshold triggered for this event for an impact speed of 15 km/sec, taken from Table 11 of [SRAMAETAL2004]. This table is reproduced in Table 1 of the HRD instrument catalog file in this data set." UNIT = "GRAM" DATA_TYPE = "ASCII_REAL" START_BYTE = 147 BYTES = 7 FORMAT = "E7.1" MISSING_CONSTANT = 0.0E+00 END_OBJECT = COLUMN OBJECT = COLUMN COLUMN_NUMBER = 28 NAME = "THRESHOLD_DIAMETER" DESCRIPTION = "The particle diameter corresponding to the THRESHOLD_MASS assuming a particle density of 2.5 g/cm^3. The values are taken from Table 11 of [SRAMAETAL2004]. This table is reproduced in Table 1 of the HRD instrument catalog file in this data set." UNIT = "MICRON" DATA_TYPE = "ASCII_REAL" START_BYTE = 155 BYTES = 5 FORMAT = "F5.1" MISSING_CONSTANT = -99.9 END_OBJECT = COLUMN END_OBJECT = TABLE END